Abstract
Removal of nitrate ion by means of endogeneous denitrification is suitable for treatment of nitrate-polluted ground water utilized as drinking water, since in the case of endogeneous denitrification, introduction of organics as proton donor is not needed.
In this case bacteria utilizes organic substances accumulated in the bacteria itself as proton donor. Thus accumulation and utilization of organics in the bacterial biomass become important processes for effective use of this function.
Uptake and accumulation of organics are measured experimentally and the conditions necessary for accumulation was determined as well as maximum accumulation capacity and uptake rate.
Also endogenous denitrification rate and capacity by using accumulated organics was determined. On the basis of these parameters, mathematical models for describing accumulation step and denitrification step are proposed and calculation was carried out for cyclic process involving repeated accumulation and denitrification steps. The reasonable agreement between measured concentrations and calculated ones suggests the possibility of application of this process to the treatment of ground water.